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Laboratory use of dogs on the upswing

Given the endlessly rising popularity of dogs, and our increasing emotional attachment to them, medical researchers who use them for experiments can expect stronger and growing opposition to the practice from the public, a leading expert in canine-human interaction told a conference at Johns Hopkins University this week.

James Serpell, director of the Center for the Interaction of Animals and Society at the University of Pennsylvania School of Veterinary Medicine, was the keynote speaker at a conference sponsored by the Center for Alternatives to Animal Testing at the Bloomberg School of Public Health.

The 30-year-old, non–profit center promotes humane science by supporting the creation, development and use of alternatives to animals in research, product safety testing, and education. It seeks ways to replace animals with non-animal methods, reduce the numbers of animals necessary, or refine methods to make them less painful or stressful to the animals involved

Serpell and other speakers both pointed out that after decades of declining, the use of dogs in medical research has increased in the last couple of years.

U.S. Department of Agriculture figures show that the number of dogs used in medical research and testing dropped from 200,000 in 1973 to 66,000 in 2007, said Tanya Burkholder, chief of the Small Animal Section at the National Institutes of Health. Now, she said, the number has risen to about 75,000 a year.

Much of the increase is likely a result of advancements in, and the promise of, gene therapy.

Ivan Pavlov

Dogs have always been a valuable research model for scientists, going as far back as Aristotle’s day. Their size, physiology and cooperative behavior have made them convenient models for scientists, who, like Pavlov’s dog, grew conditioned to using them in experiments.

While public opposition to subjecting dogs to medical experiments resulted in the practice dwindling in recent decades, the use of dogs has crept up again in the last two years due to advances in molecular biology, genetics and the sequencing of the canine genome.

Because dogs get about 220 of the same inherited diseases and disorders that humans do — including Alzheimer’s, muscular dystrophy, hemophilia and retinal degeneration – medical researchers are able to study the underlying genetic defects and, through dogs, seek cures.

This means dogs are being bred to be born with the diseases in colonies at U.S. universities and research institutes and, in the case of South Korea, cloned to be born with the diseases.

No one at the conference went so far as to suggest a halt to using dogs in research, but Serpell warned that the practice does come with risks, and a price.

Dogs evoke protective and nurturing instincts in people, and those have grown stronger as the dog-human relationship has evolved — to the point that dogs are viewed more as family members than family pets. Public opposition to the laboratory use of dogs has continually grown in the last few decades.

Researchers need to be cognizant not just of society’s strong feelings about dogs, but also about dog’s strong feelings for humans, Serpell said. “Many dogs undergo severe distress when contact with a human is limited or thwarted. We don’t give that regard sufficient credence,” he said.

The stronger attachment to dogs is in part due to breeders focusing on creating animals for purposes of human companionship, unlike in the past when they were bred for the work they could do. Serpell noted that baby-like features, for one thing, appeal to humans.

Showing photos of dogs, Serpell pointed to one and said, “This animal looks like it was invented by Walt Disney.”

Our attraction to dogs stems too from the fact that they make eye contact with humans more than any other species, and studies have shown that petting, or even looking, at a dog increases our levels of oxytocin.

“These dogs are turning us on by looking at us,” he said.

Our evolving closeness to dogs has implications for the laboratory, he noted, and perhaps all of society.

Serpell pointed to commentator Tucker Carlson’s recent statement that dogs are the social equals of humans, and that therefore Micheal Vick should have been executed for killing them.